The Sonic Metal Air Caulking Gun (ST-6640) is a robust pneumatic dispensing tool constructed with a full metal body to deliver professional-grade caulking performance. Ideal for use with standard 310 ml cartridges of silicone or other sealants, this gun offers continuous, consistent flow and precise control - perfect for sealing gaps, joints and cracks in construction, glazing, automotive, marine and general industrial applications. Its ergonomic pistol-grip design reduces operator fatigue, while the 1/4″ air inlet and reliable internal mechanism ensure stability and durability under rigorous use. Backed by a 3-month warranty, it is built to serve contractors and tradespeople who require effective, high-throughput sealing performance.
Features
:- Durable metal construction : The body of the tool is built primarily of metal, offering long service life and resistance to wear.
- Cartridge compatibility : Designed for use with standard 310 ml cartridges of silicone or similar sealants.
- Optimised bore & tube length : Specification lists show a 2" × 8½" bore/tube length and overall length of 12".
- Air-powered operation : This pneumatic caulking gun leverages air pressure for smooth, controlled dispensing rather than purely manual force.
- Precise flow control : Because it’s air-driven, the user can fine-tune the flow rate of sealant, reducing waste and improving finish quality.
- Ergonomic pistol-grip design : The handle style reduces operator fatigue during extended use.
- Versatile use across materials : Suitable for sealing on substrates such as glass, metal, concrete, wood, plastic and rubber when used with appropriate sealants.
- Industrial-grade performance : Suitable for demanding jobs (e.g., curtain wall sealing, vehicle assembly, marine sealing).
- Quick set up & easy cartridge loading : Designed for fast tip-cutting, nozzle fitting and cartridge insertion so you can get to work quickly.
- Warranty protection : Comes with a 3-month warranty (as stated in your description) to cover manufacturing faults or performance issues.
Applications
:- Sealing gaps and cracks around window and door frames
- Applying silicone joint sealant in kitchens, bathrooms and wet areas
- Filling expansion joints in concrete, masonry and precast panels
- Automotive bodywork sealing and adhesive application
- Marine sealing tasks (hulls, fuel tanks, underwater components) when paired with suitable marine-grade sealant
- Curtain wall and façade construction - applying sealants between glass, metal mullions and structural elements
- General industrial assembly where adhesives or sealants are used in cartridge form
- DIY and renovation jobs: bath-tubs, sinks, tiled surfaces, roofing leaks
Usage
:- Ensure your air supply meets the required specification (typically 45–90 psi for similar models) and use a clean, dry, regulated line.
- Cut the tip off your sealant cartridge and attach the correct size nozzle for the bead width you require.
- Insert the 310 ml cartridge into the gun’s barrel. Secure the retaining collar or cover ring as required.
- Connect the air hose to the 1/4″ inlet and ensure the gun is stable.
- Pull the trigger to dispense sealant, adjusting your bead speed and width by regulating air flow or nozzle diameter.
- Maintain a steady hand and consistent speed to achieve a uniform bead without gaps or voids.
- After use, clean the tool: relieve air pressure, remove the empty cartridge, wipe off any excess sealant from the nozzle and gun body, and store the gun in a dry, protected place.
- If the tool will be idle for several days, many manufacturers recommend a few drops of pneumatic tool oil in the inlet prior to next use.
- Observe the warranty terms : the 3-month warranty typically covers manufacturing defects but not wear and tear, misuse or damage from foreign materials - record the purchase date and keep the warranty card.